Shelf extending and lifting system

ABSTRACT

A cabinet having opposing side walls and an open, or openable, frontal area, provides a pair of arms pivotally engaged with each of the side walls. The arms are rotatable between a downwardly and rearwardly directed position within the cabinet for storing a shelf or basket attached to the arms, and a forwardly directed position extensive of the frontal area for exposing the shelf or basket. Each of the pair of arms is, in one embodiment of the invention, engaged with a guide plate fixed at one side of a basket, whereby the basket is able to move between a retracted position inside the cabinet, and a frontally extended and raised position. Such movement is facilitated by a motor driven linear actuator. In another embodiment, the arms are spring loaded, and in a still further embodiment, the arms are connected with a linear draw slide.

RELATED APPLICATIONS

none

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to apparatus for moving a shelf to a desired vertical position, and more particularly to an improved mechanical enablement for such.

2. Description of Related Art

The following art defines the present state of this field and each disclosure is hereby incorporated herein by reference. Of particular relevance are:

Schneller, U.S. Pat. No. 3,857,623 describes an aaccessory with parallel linkages for swingably mounting an intermediate shelf of a kitchen cabinet o the like, to permit lowering it in height for easier access. Either a return spring or a compression washer which is progressively compressed by lewering movements is used to resist lowering movement. The arms of the linkage are offset. These linkages are applicable also to an entire cabinet.

Vogelgesand et al, U.S. Pat. No. 5,308,158 describes a pull down shelf assembly for facilitating access to upper storage shelves. The shelf assembly includes a shelf guide track mechanism and the storage shelf slidably mounted for movement between an extended position and a retracted position. A pantographic pull down mounting assembly coupled between a shelf mounting bracket and the track mechanism produces pantographic movement thereof between a deployed position, for increased access, and an elevated stored position. The pantographic assembly is mounted therebetween at locations producing near-horizontal pantographic movement of the track mechanism with the storage shelf carried thereby throughout an arcuate path between the deployed position and the elevated stored position. A spring biasing mechanism coupled between the mounting bracket and one of the arms biases the track mechanism toward the stored position. A shelf locking mechanism, positioned between the track mechanism and the storage shelf, locks the storage shelf in the extended position during movement of the track mechanism from the deployed position to the elevated stored position.

Geiss, II, U.S. Pat. No. 5,586,816 describes a mobile storage cabinet in combination with a shelf structure horizontally and vertically adjustable with respect to the cabinet. In a first embodiment, the shelf structure comprises an inner cabinet having vertically spaced shelves slidingly mounted therein. In the stored position, the inner cabinet including shelves resting inside the outer cabinet beneath the top surface thereof; in the extended position, the inner cabinet rests forwardly of the outer cabinet and may be further moved vertically between fully lowered and raised positions. In a second embodiment, a unitary shelf is horizontally and vertically adjustable with respect to the cabinet, this embodiment being especially useful as a work table while the first embodiment is especially useful for transporting and storing equipment.

Other U.S. references which are somewhat related to the present invention include: U.S. Pat. Nos. 4,076,351, 4,026,434, 4,893,885, 4,915,461, 5,228,763, 5,249,858, 6,857,756, 6,209,405, 6,247,771, 6,367,898, and 6,523,919.

Foreign and international references which are somewhat related to the present invention include: JP7008339, JP9154643, JP9327338, JP2000270936, JP2001070063, JP2001178555, JP2002078540, JP2003102561, and WO97/00631.

Therefore, our prior art search teaches: a motor driven hoisting and lowering type upper cabinet with contact stopping function, a lift for storing a shelf, a lifting and lowering cabinet, a supporting device for lifting and lowering of a cabinet, a lift-type cabinet, a raising-lowering shelf device of a desk or the like, a lifting storage shelf, an apparatus for transferring a carrier for shelves, cupboards, tables or the like along a path, a lift shelf, a filing cabinet having vertically extensible drawers, a cabinet assembly, an apparatus for transferring a carrier for shelves, cupboards, tables or the like along a path, a lifting and lowering device for furniture elements, a multi-purpose, mobile storage cabinet with horizontally and vertically adjustable shelf structure, a pull-down storage shelf assembly, a motor driven movable cabinet, an extendable storage element, a modular kitchen unit, a swing down closet, a swingable shelf assembly for cabinets. Thus, the prior art shows that it is known to provide mechanical means for raising and lowering a shelf, and furthermore to move the shelf from a retracted position to an extended position prior to raising it (Geiss, II). However, the prior art fails to teach the improved mechanism of the present invention, in each of its embodiments, for moving a shelf horizontally in a first phase and then vertically in a second with simple automation and raising arm linkages. The present invention fulfills these needs and provides further related advantages as described in the following summary.

SUMMARY OF THE INVENTION

The present invention teaches certain benefits in construction and use which give rise to the objectives described below.

The invention is generally used for kitchen cabinets, dishwashers and the like. Specifically, the invention is an appliance lifting system that raises a lower shelf or under-counter cabinet up to the counter level with the intention of making it easy for a user to load and unload the shelf, or in the case of a dishwasher, a basket. The system is directed to the lower shelves of cabinets or generally, shelves that require a user to bend or stoop down to load or unload. The system comprises two set of elongated levers or arms, each set arranged in a parallelogram configuration fastened on one end to a cabinet sidewall and on the other end to the lower cabinet shelf or basket. The arms in each set are connected to one another by a combination of pivot pins and pin and slot sliding connections in the primary embodiment. The system operates in two phase motion. During the first phase, the system linearly and horizontally slides the shelf out of the cabinet. In the second phase, the system raises the shelf in an arcuate motion out and upwards to counter level. In use the operation of the system may be by manual pushing or pulling of the shelf with spring assist, or by motor driven arms that accomplish the intended motion automatically. The later approach is considered to be the preferred embodiment and will be described in detail below.

A primary objective of the present invention is to provide an apparatus and method of use of such apparatus that yields advantages not taught by the prior art.

Another objective of the invention is to provide an automated system to raise a lower shelf or basket to counter level for ease of loading or unloading articles therein.

A further objective of the invention is to enable such an automated system with a limited number of parts so as to achieve practical cost effectiveness in a finished product.

A still further objective of the invention is to enable such an automated system that is able to provide both shelf extension and shelf raising and lowering using a single set or pair of actuators and mechanical engagements.

Other features and advantages of the embodiments of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of at least one of the possible embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate at least one of the best mode embodiments of the present invention. In such drawings:

FIG. 1 is a perspective view of a preferred embodiment of the invention showing a basket of the invention in a retracted position;

FIG. 2 is a partial enlarged view thereof, showing details of lifting arms of the invention;

FIG. 3 is the same view as FIG. 1 but showing the basket in an extended position;

FIG. 4 is a partial enlarged view thereof showing details of a basket guide plate of the invention;

FIG. 5 is a side elevational view thereof showing a door in a folded down position, the basket in a raised position and details of a lifting mechanism of the invention;

FIG. 6 is an partial enlarged perspective view thereof showing details of the lifting arms with the basket in the raised position;

FIG. 7 is a partial perspective view of the lifting mechanism shown in FIG. 5; and

FIG. 8 is a schematic diagram of an alternate lifting arm arrangement of the invention using springs to assist shelf or basket movement and drawer slides for extension and retraction of the shelf or basket.

DETAILED DESCRIPTION OF THE INVENTION

The above described drawing figures illustrate the present invention in at least one of its preferred, best mode embodiments, which is further defined in detail in the following description. Those having ordinary skill in the art may be able to make alterations and modifications in the present invention without departing from its spirit and scope. Therefore, it must be understood that the illustrated embodiments have been set forth only for the purposes of example and that they should not be taken as limiting the invention as defined in the following.

In a first embodiment of the present invention a cabinet 10, such as a dishwasher cabinet, or a kitchen cabinet, has opposing side walls 12 and 14, with each of these side walls 10 and 12 having an interior wall surface 15 as shown in FIG. 1. Clearly, such a cabinet preferably also has a top, back and bottom panels as shown. Further, the cabinet 10 has an open frontal area 20 which may be closed or opened by door 11 which is hinged along its bottom edge 11′, as shown in FIG. 5. Pivotally engaged at their proximal ends, with each of the side walls 12 and 14, is a pair of lifting arms 30 and 32, and these arms are positioned for rotation about the pivotal joints at their proximal ends, adjacent to their respective interior wall surfaces 15, i.e., moving in planes parallel with the wall surfaces 15. The lifting arms 30 and 32 are rotatable between a downwardly and rearwardly directed position 40 within the cabinet 10 as shown in FIGS. 1 and 2, and a forwardly directed position 45 extensive of the frontal area 20, as shown in FIG. 3. Each of the pairs of arms 30 and 32 are further pivotally engaged at their distal ends, with a guide plate 60 fixed at each side of a basket 70, whereby the basket 70 is able to move between a retracted position (arms 30, 32 in position 40) placing it fully inside the cabinet 10 (FIGS. 1 and 2), and a frontally extended position (arms 30, 32 in position 45) as shown in FIG. 3. Further, the arms 30, 32 may be moved to a raised position 50 as shown in FIGS. 5 and 6 wherein the basket 70 is raised also to counter top level. A means for driving 80 of at least one of the arms 30 or 32, of at least one of the pairs of arms is engaged for executing these basket movements and for raising the basket to position 50, as shown in FIGS. 1 (position 40), 3 (position 45), 5 and 7 (position 50). The use of the term “basket” in this description shall also include and refer to shelves, trays and other types of article holding or storing elements. While the term “basket” is commonly use to describe a shelf in a dishwasher apparatus, it is noted here that the invention is not limited to such apparatus.

In one enablement, shown in FIGS. 1-7, the arms 30 and 32 of each of the pairs of arms are pivotally interconnected by a strut 33, the strut acting to stabilize the arms 30 and 32 and maintain them in parallel alignment, as they move over their course of motion. Preferably, the guide plates 60 each provide a pair of slots 62 and 64, and the arms 30 and 32, at their distal ends, are adapted for being captured while being enabled for sliding motion within these slots 62 and 64 respectively as best seen in FIG. 4. Such adaptation preferably includes rollers 65 which are able to move in the slots 62, 64 with near frictionless sliding and roller motion. The slots 62, 64 enable the arms 30, 32 to be fixed in length while they move circumferentially about the proximal pivot points.

In an alternate embodiment, shown schematically in FIG. 8, each of the arms 30′ and 32′ function nearly identically to arms 30, 32, but further comprise a pair of arm segments 34 and 36. The arm segments are telescopically joined for axial extension and retraction as the basket 70 moves between positions 40 and 50, as previously described. The arms 30′ and 32′ preferably further comprise an extension spring 39, as shown, positioned for urging arm segments 36 to extend from arm segments 34 so that the basket 70 is forced to maintain its lowest position as it is extended (pulled out) from its initial position 40. When the arm segments 36 are fully extended, the basket 70 is fully extended from the cabinet 10 (position 45), and is ready to be raised to position 50. The springs 39 help maintain the basket 70 in its fully retracted position 40 within the cabinet 10, and also, as shown in FIG. 8, help the basket 70 to move to its fully extended position 45. In this embodiment, therefore, the driving means 80 may be employed only for raising the basket 70 from position 45 to position 50, a less complex approach then the first embodiment described above. Of course the driving means 80 may, by choice, be used as described for moving the basket over its full range between positions 40 and 50. In this embodiment, the guide plates 60 need not have slots 62 and 64, as the arms 30′ and 32′ are able to change length as necessary, so that the distal ends of arms 30′ and 32′ may be simple pivotal joints.

In a further alternate embodiment, shown schematically in FIG. 8, the arms of either of the two embodiments described above may be used with telescoping draw slides 90 and 92, where the basket 70 is engaged with an inner one of the draw slides 92, and the arms 30, 32, or 30′, 32′ are distally engaged with an outer one 90 of the draw slides. In this case, the basket 70 is able to be pulled-out of, and pushed-into, the cabinet 10 in a manner identical to that of a common dresser drawer, and for raising the basket 70, at least one of the arms 30, 32 or 30′, 32′, is engaged by the driving means 80 to raise the draw slides 90 and 92 and the basket 70 in the same manner as described above. When arms 30, 32 are used in this embodiment, it is clear that the guide plate 60 is mounted to the outer one of the slides 90.

The driving means 80 is preferably a motor 82, such as a small electric gear-motor engaged by gears (not shown) with a linearly extensible strut 84 such as a worm gear linear actuator, well known in the art. The driving means 80, preferably includes limit switches 86 positioned for disengaging power to the driving means 80 when the basket is in its initial position 40, as shown in FIG. 1, and in its extended 45 and raised position 50, as shown in FIGS. 3 and 6 respectively. The simple electrical circuit necessary for controlling the driving means 80 would be known by those of skill in the art and may, for instance, be adapted to move the arms 30 and 32 or 30′ and 32′ between positions 40 and 50 without stopping at position 45, as a choice, or between positions 40 and 45 independently of moving between positions 45 and 50 as a choice. Clearly, to enable such, micro-switches 86, 86′ and 86″ are positioned for sensing when the driving means 80 has attained any one of the positions 40, 45 and 50 respectively. As shown in FIGS. 1, 3 and 5, leverage bar 85 is pivotally joined to extensible strut 84 at its distal end so as to provide torque leverage to pivot 87 which is joined to arm 32 or 32′. Clearly, as shown in FIGS. 1 and 5, the driving means 80 is configured in mirror image on both sides of cabinet 10 so that the opposing arms on both sides are driven simultaneously for uniform motion actuation of basket 70. Also, the driving means may be configured for mounting within the cabinet 10, within the side walls 15 of the cabinet 10 or externally as shown in the enclosed figures.

The enablements described in detail above are considered novel over the prior art of record and are considered critical to the operation of at least one aspect of one best mode embodiment of the instant invention and to the achievement of the above described objectives. The words used in this specification to describe the instant embodiments are to be understood not only in the sense of their commonly defined meanings, but to include by special definition in this specification: structure, material or acts beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, then its use must be understood as being generic to all possible meanings supported by the specification and by the word or words describing the element.

The definitions of the words or elements of the embodiments of the herein described invention and its related embodiments not described are, therefore, defined in this specification to include not only the combination of elements which are literally set forth, but all equivalent structure, material or acts for performing substantially the same function in substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the invention and its various embodiments or that a single element may be substituted for two or more elements in a claim.

Changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalents within the scope of the invention and its various embodiments. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. The invention and its various embodiments are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what essentially incorporates the essential idea of the invention.

While the invention has been described with reference to at least one preferred embodiment, it is to be clearly understood by those skilled in the art that the invention is not limited thereto. Rather, the scope of the invention is to be interpreted only in conjunction with the appended claims and it is made clear, here, that the inventor(s) believe that the claimed subject matter is the invention. 

1. An apparatus comprising: a cabinet providing opposing side walls, each of the side walls having an interior wall surface, the cabinet further providing an open frontal area; pivotally engaged with each of the side walls, adjacent the respective interior wall surface, a pair of arms rotatable between a downwardly and rearwardly directed position within the cabinet, and a forwardly directed position extensive of the frontal area; each of the pair of arms further pivotally engaged with a guide plate fixed at one side of a basket; whereby the basket is able to move between a retracted position inside the cabinet, and a frontally extended and raised position; and a means for driving at least one of the arms of at least one of the pair of arms for executing said basket movement.
 2. The apparatus of claim 1 wherein the arms of each of the pair of arms are pivotally interconnected by a strut.
 3. The apparatus of claim 1 wherein the guide plates each provide a pair of slots, each of the pairs of arms adapted for sliding motion within the slots.
 4. The apparatus of claim 1 wherein each of the arms comprises a pair of arm segments, the arm segments telescopically joined for axial extension and retraction.
 5. The apparatus of claim 4 wherein each of the arms further comprises an extension spring positioned for urging one of the arm segments to extend from the other of the arm segments.
 6. The apparatus of claim 1 wherein the driving means is a motor engaged with a linearly extendable strut.
 7. The apparatus of claim 6 further comprising a limit switch positioned for engaging the driving means whereby power is terminated to the motor when the basket is in one of a retracted, extended and raised position.
 8. The apparatus of claim 1 further comprising a set of draw slides engaged with the basket and with the arms, the draw slides enabled for moving the basket linearly into and out of the cabinet, the pairs of arms enabled for lifting the draw slides and the basket to a raised position. 